\section{Conclusion}
\label{sec-conclusion}

\sys is a library that gives back to researchers the ability to
evaluate the scalability of large storage systems. \sys is based
on the \scheme compression scheme, which leverages a specific
data format to achieve efficient compression and high degrees of 
colocation, which in turn allows researchers to perform large-scale
experiments on as few as one hundred machines. We have used \sys
to identify several performance problems in HDFS and HBase. Fixing
these problems allowed the system to significantly increase its
maximum achievable throughput.
